The United States-led invasion of Iraq represents the first application of a new national security policy that has come to be known as the Bush doctrine, after President George W. Bush. The Bush doctrine signals a radical break from previous national security strategies and fundamentally changes the way the United States may act toward the rest of the world.

This brief guide is intended as a starting point toward understanding the Bush doctrine and recent shifts in U.S. national security policy. It also provides links to related information in Encarta Encyclopedia.

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The end of deterrence and containment
For almost 50 years, following the end of World War II (1939-1945) and the beginning of the Cold War, U.S. foreign policy rested on the concepts of deterrence*  and containment*. In a world dominated by two superpowers, the United States and the Union of Soviet Socialist Republics (USSR), both armed with huge arsenals of nuclear weapons and other weapons of mass destruction, the policy of deterrence relied on mutual assured destruction (MAD) to prevent the outbreak of a major war.

The policy of containment, first outlined by diplomat George Kennan in "The Sources of Soviet Conduct,"* represented the second pillar of U.S. foreign policy. It argued for the use of diplomacy backed by sufficient strength in conventional military forces to protect U.S. interests and prevent the USSR from expanding its realm of influence. (See Thematic Essay: History of American Foreign Policy.*)

With the end of the Cold War and the breakup of the Soviet Union in 1991, the United States emerged as the world's sole superpower. Nevertheless, during the administrations of Presidents George H. W. Bush and Bill Clinton, U.S. foreign policy continued to rely on concepts of both deterrence and containment.

Justification for the Bush doctrine
All this changed under the administration of George W. Bush, and the full contours of the new Bush doctrine became apparent in September 2002 with the publication of "The National Security Strategy of the United States." As outlined in this position paper, U.S. foreign policy rests on three main pillars: a doctrine of unrivaled military supremacy, the concept of preemptive or preventive war, and a willingness to act unilaterally if multilateral cooperation cannot be achieved.

President Bush argued that the new policy was necessary to prevent the proliferation of weapons of mass destruction among rogue states and terrorist groups. The policy of deterrence, he maintained, was no longer sufficient to prevent a rogue nation or terrorist organization from using nuclear, chemical, or biological weapons.

In line with the new policy, the Bush administration in 2002 withdrew from the Anti-Ballistic Missile Treaty, known as the ABM Treaty, and called for the creation of a missile defense shield for the United States by 2004. (See Air Defense Systems*; Arms Control.) The administration also sought substantial increases in defense spending. By 2005 the U.S. defense budget will be greater than the defense budgets of the rest of the countries of the world combined.

Origins of the Bush doctrine
Although the Bush doctrine was not publicly articulated until September 2002, its origins actually go back to the early 1990s. In 1992, a document written at the direction of Richard Cheney, then the secretary of defense, first introduced the idea that the United States should never again allow another rival superpower to emerge. When the contents of the document were leaked to the press, however, it was disavowed.

One of the authors of the document, Paul Wolfowitz, later joined with a group of neoconservatives who formed an organization called the Project for the New American Century (PNAC). Among the founders of the PNAC in 1997 were men who later became key policymakers in the administration of George W. Bush. They included Vice President Cheney, Defense Secretary Donald Rumsfeld, and Deputy Defense Secretary Wolfowitz. Among PNAC's most prominent actions was an open letter addressed to then-President Clinton, calling for "the removal of Saddam Hussein's regime from power" and the use of force, if necessary, to remove him. That goal became policy soon after Bush took office and before the terrorist attacks of September 11, 2001.

Criticism of the Bush doctrine
The Bush doctrine, however, has met with significant criticism. The arguments against the doctrine, expressed both before and since the invasion of Iraq, accuse it of leading the United States to act unilaterally and to behave arrogantly. The United States risks alienating world opinion, critics of the doctrine say, thereby jeopardizing the international cooperation essential to hunt down terrorist organizations.  The doctrine of preemptive war, these critics add, is likely to encourage rather than discourage the proliferation of weapons of mass destruction and if adopted by other nations, could increase the likelihood of regional conflicts.

Two of the most prominent critics of the Bush doctrine are former national security advisors Brent Scowcroft, who served under President George H. W. Bush, and Zbigniew Brzezinski*, who served under President Jimmy Carter. An open policy of preemptive war, Scowcroft told the media, "tends to leave the door open to others who want to claim the same right. By making it public, we also tend to add to the world's perception that we are arrogant and unilateral." Brzezinski echoed a similar theme, saying, "Our doctrine of preemption may encourage others to preempt their neighbors, thereby legitimating increasingly indiscriminate use of power."

Those "others" might include countries with nuclear weapons. Currently, both India and Pakistan have nuclear weapons, and relations between the two countries are tense. If one or both of these countries adopted their own version of the Bush doctrine, the resulting destabilization might lead to a nuclear holocaust. Alternatively, critics of the Bush doctrine say, a nonnuclear state fearing a preemptive attack from the United States or another powerful country might decide that its only recourse was to seek weapons of mass destruction for self-protection. A spiraling arms race could ensue that would wreck the Nuclear Nonproliferation Treaty. (See Nuclear Arms After the Cold War*.)

Finally, as some so-called realist critics of the Bush doctrine argue, history demonstrates that nations tend to seek a balance of power. (See International Relations*.)  By asserting that it intends to prevent other countries from "surpassing, or equaling, the power of the United States," these critics say, the Bush administration is simply encouraging other nations to band against America. They point to the fact that the first application of the Bush doctrine has already led to a rupture in relations with several long-standing allies, such as France and Germany, and was opposed in the United Nations Security Council by China and Russia.

Both opponents and proponents of the Bush doctrine, however, are likely to agree on one thing. It is the most radical change in U.S. foreign policy in more than 50 years, and it has led the United States to wage the first preemptive war in its history. 

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